In 1940s London, Juliet Armstrong works in the Home Office and is also an undercover agent for MI5. As part of her work to monitor British fascist sympathisers, she infiltrates the Right Club and finds herself at an Odeon cinema with fellow agent, Giselle, watching Gaslight. At the end of the programme, she has to sing along with a right wing, anti-semitic rendition of ‘Land of Hope and Glory’.

Gaslight, from which the term gaslighting originates, was directed by Thorold Dickinson in 1940 and based on Patrick Hamilton’s popular 1938 play. It was remade in Hollywood in 1944 by George Cukor starring Ingrid Bergman and Charles Boyer.

As befits a psychological thriller of deception and betrayal, Juliet takes an earlier trip to the cinema for a matinee screening of Hitchcock’s Rebecca at the Curzon in Mayfair, after she had ‘looked around the shops and had a pot of tea and a slice of walnut cake in Fuller’s in the Strand.’ The Curzon in Mayfair is one of the capital’s cinema jewels and currently under threat of closure. Rebecca, based on Daphne du Maurier’s novel, was Hitchcock’s first film in Hollywood, made in 1940.